Bound-edge plaster wall board



May 31, 1927;

. C. W. UTZMAN BOUND-EDGE PLASTER WALL oARD Original Filed March-14,1923 N V lf N TUA ga/ence M Uzman.

1 TTORNEY forth of the bottom sheet` are of such stillness 'that vtheyare singularly depressed from the bend at, the top corner of the edge,when the edges are scored to form the corners as set v p in my Patents1,330 413 of February '10, 1920 and 1,383,249 of i une Q8,l1.921,'although the upper corner itself liesiin the plane of the uppersurface ot' the top cover sheet there is a slight longitudinal' edge'deepening from the corner of the edge ot the board to the bottom of thelongitudinal edge of the top sheet,

' which depression varies in Width'in accordof thickness Will he ancewith the slightvariations vof the position of lthe top cover sheetcaused by the variations ot' the width of the paper and the slightWeaving of the paper in the machine before. it is applied to the board.4

0n account vof these depressionsalong each longitudinal edge the topsheet side ol' the boardmust be applied next to the studding" to presenta. smooth exterior surface to the wall or ceiling. It has also beenfound in the practicall manu'larture o'l plaster walllioard inaccordance with patents heretovfore mentioned that,thecoi'isistency o'l`the plastic mixture `for thel core duo to mechanicut limitations otvmael'iinery at times is thicker than at other times, which results inthe plastic-core mass not uniformly and completely entering .between thetop ot the folded over liap and under side ot' the longitudinal marginol' the top rover sheet as the board passes unifier the forming roll andsmoothing or ironing devices thereafter and also at times causes theedge ol' the top sheet to project above the ad "aeent upper eorner ofthe edge ol' the board). The etl'ect olj this is that there are hollowspaces lett between the covering sheets under the muigine adjacent theedges oi the top sheet so that when the wallboard is applied with thetop cover sheet side against the stud and nailed thereto, the drivingot' the nail through such hollow spaces causes themurv gin ot' thewallboard at that point to be drawn against the stud belou1 the exteriorsurface of the adjacent wallboard and at times bends the margin at suchedge 'for a substantial distance abutting the uniiorni edge ot' theadjzu-ent Wallboard upon the exterior wall surface.v

This invention contemplates Various related means for producingn plasterwallboard that will be ol throughout. that is the exterior dimension thesame througl'iout. each longituiilinal hound edge of each wall- ,boardso that all portions of each side surface Will lie in the samerespective plane. In. such a Wallboard either side may form the exteriorof the wall and it will not be necessary to place one particular sideagainst the-studding and as each longitudinal edge when nailed to thestudding will uniforn'ily depression along each `lines where its 'boardscorings of the top ythe bottom sheet may causing a ilepressionuniformthickness' engage the stud throughout so that the ex'- terior surfacesofthe abutting edges ot adjacent Wallboards will lie in the same planeand the surface ot' the entire wall althoul' madeup otsections ofwallboard will uniformly smooth.- j

One form of this invention is illustrated in Figure 1 in which thebottom cover sheet 1 is folded to envelop the longitudinal edges of theplastic composition oore 2l with the margins 3 of the edges ol thissheet lying upon the top ot' the core, and thevtop cover sheet 4 is ofsuiiieient Width to be folded about the longitudinal covered edges ofthe wallboard to embrace the margins of the bottom. cover sheet and besecured thereto. It is preferable to score the bottom sheet along thelines Where the bends in the folds ofthe margins form the corners of theboard before the top sheet is applied and it is also preferable to suorethe top sheet along the margins fold over the core edge envelopingportions of the bottom sheet to provide square corners. It is preferableto accomplish this scoring of the top covelt sheet just before it'isapplied to the Wallso that there will be an exact register with thecorners or' the bottom sheet when the top sheet is folded thereover. Themar gine (S to the top sheet are ehamfered orbeveled so that they taperfrom the bottom rorner scot-ings to their respective edges. The scoringsare so arranged on each side of the bottom sheet that the correspondingsheet Will fold about the edges and will be the desired thickness of thewallboard.

It is preferable tov apply the top sheet and fold its margins about thelongitudinal edges before subjecting the Wallboard With. its core inplastic condition to the final press sure that determines and maintainsthe uni`- vterm thickness, which pressure will also align the foldedover margins of the to'p sheet in the same plane with the main portionot.' the bottom sheet. The portions of the top sheet contacting withlportions of be secured or bonded thereto throughout the contact or anyportion thereof by a film ot' the plastic body material or by anadhesive, such 'as silicate or soda, or by a combination of both. Asaforesaid, it is preferable to accomplishv the scoring ol the top sheetjust before it is applied, it is also preferable to chamferor bevel themargins of the top sheet at the same time or just after the scoring sothat the margins will taper from the outer scored lines to theirrespective edges, and varia.- tions in the width of the paper will noteffect the finished wallboard because the scorings of the 'top andbottom sheets are so arranged that the outer top sheet will embrace thecorners of the bottom sheet fold and the nal pressure in applying thetaper- WW.

inf margins ofthe top sheet on the under si e of the bottoni sheet `willcause the angular portions 6 adjacent the innermost scoring of thebottom sheet to be adjusted in accordance with the amount of'top sheetniargin applied'thereover. It it is desired to maintain the margins `3of the .bottom sheet against the under portions of ,theenvcloping. topsheet, the margins may be slit preferably at right angles to the ed ressulficientl'y7 to form tongues 7 bent at'rig 1t angles thereto .andwhich'vvill ,enterA the composi- 'tion body asithe'margins are'foldeddmvn thereove'r and prevent the -folded over portions lbecomingdepressed intothe plastic core In this form of this invention ltheWallboard is reversible, Will enfage the stud throughoutitslongitudinal-cringe, and. ossesses doubly protected longitudinal e gesand edge corners.

A moditication'is shown in Figures 4 and 5 in which the top cover sheetis cut wider than the 'desired lWidth ofthe wall board. The top sheeetis scored 'preferably just be fore the sheet is applied to the vplasticcore after the margins 3 of bottom cover sheet l have been :folded overto lieupon the top of the core. The scoring of the top sheet forms thetop corners of the longitudinal edges and ,is arranged above thescorings of the bottom sheet that forms the lower corners of thesaidedges. The margins 9 of the top sheet-are chamfered or beveled so thatthey 'Will-taper from the scorings to their respec tive edges and whenfolded down against the edge coveringthe portion of the bottom sheetwill torni rectangular longitudinal edges i upon the wallboard. Thescorings upon the bottom sheet are so arranged that theouterinost'scorings will allow the bend within the top cove-r sheet tobeniade within the desired thickness of the'wallboard. The contactingportions of the bottom and top lsheets may be bonded or secured by afilm of the plastic body material or by. an applied adhesive throughoutthev entire contact or by any conilbination of these desired. This forniof tit) 'Wallboard isreversible and'ofuniforrn thick 4and secured at itsmargins t ereto, said margins chamfered vto bring the exterior` surfacesthereof into the plane of the main body "ofsaid lirst sheet, and theinner cover sheet edge being formed with spaced tongues which extendtransversely rvithin the walk` board'to support the opposite coversheets .at their edges.

2'. A :laster wallboard having al composition bo ywith fibrous coversheets thereon, one of. said cover sheets passing about the longitudinaledges of thewallboard to en gage the vopposite side thereof with theother cover sheet extending beyond vthe side it covers and'passiug ontothe said edges with its margins secured to the first sheet, sald marginschaxniered to bring the exterior surfaces thereof into the plane oftheother sheets, and a series of tongues formed in the edge of the innercover sheet toextend transversely in the Wallboard to 'strenghten theedges thereof.

3. A'plaster wallboard having a composition. body with fibrous coversheets thereon,

one of said cover sheets passing about the-` longitudinal edge of theWallboard with the margin engaging the opposite side thereof, and aseries ot' tongues extending from the edge oi' one of' the cover sheetswithin the composition'body for supporting the-cover sheet opposite saidmargin. t

4l. Av plaster wallboard having the composition body with iibrous coversheets tliereon, one of said cover sheets passing about the longitudinaledge of the Wallboard with the margin engaging the opposite sidethereof, said margin provided with. integral spacedy means inwardlyextending therefrom forsupporting the opposite portion of the saineysheetin contact with the other cover sheet.

- 5. A plaster wallboa-rd having a composition body with lihrous coversheets thereon, one of said` cover sheets passing about the longitudinaledges of the wallhoard with margins enfaging the opposite side thereofwith the ot er coversheet extending about said edges over said firstsheet to engage the opposite side and secured at its mar ins thereto,said margins of the first cover s leet being provided with vtonguesextending through the composition body to the main portion of thats'ieetl to maintain v.said margins a fainst the under side of the secondcover s ieet. n

6. A plaster wallboard having a com osi`v tion body with fibrous coversheets, bot of which extend about the longitudinal edges of theWallboard, the inner sheet having an integral portion comprising spacedtongues extending transversely within the composition body to supportthe opposite portion of the same sheet.

7 A plaster wallboard having a composition body with fibrous coversheets, one of which passes about the longitudinal'edge to engage theopposite side thereof and havingv integral spaced tongues extending fromits edge Within the wallboard Ato engage and support the portion of thesaine sheet which is on the opposite face of the wallboard.

nis

A laster wallboard having e ycomposition bo y with fibrousy coversheets.both of which extend about the longitudinal edges of .the wallboard undoverlap on 'oppositel sides thereof,l thel inner sheet` having integralton ues extending tronuts edge across withv 1n he composition body to'engageuud sup-v y `poxtthe opposite portions of both sheets where' theyoverl'a y 9. A plaster wa Iboard having, composition bodywithfibrouscovel" sheets both of l which extend about the longitudinal'edges of the exterior the wallboard and overlapon opposite sides thereofthe inner sheet having A:integral CLARENCE UTZMANJ forming a strut forbplane y

